According to the American College of Radiology (ACR), if you should have an X-ray just prior to conception, there is no risk to you or the soon-to-be-baby.
If you were to have an X-ray in week three or four, the risks are probably zero at less than 10 Rads (Rads is a measure of radiation dose). If it is more than 10 Rads that indicates a possible miscarriage. In weeks five through ten, but between 5-10 Rads, they say potential effects are scientifically uncertain and probably too subtle to be clinically detectable. Over 10 Rads and the chances of malformations increase with the dose. In weeks eleven through seventeen, at the 5-10 Rad dose potential effects are scientifically uncertain and probably too subtle to be clinically detectable.
Though ACR notes that you can have IQ damage over the 10 Rad mark, increasing with exposure. Once you hit weeks 18-27, you do not see issues with X-rays until you hit the greater than 10 Rad dose. After week 28, the risks are the same to the baby as the mother. Doses less than 5 Rad are always considered to cause no issues at any point in pregnancy.
While this may all sound very upsetting, the vast majority of plain X-rays, like the kind you had have for a broken bone or at the dentist's office, have few low doses of radiation. In fact, you would need more than 20 abdominal X-rays to hit the 5 Rad dose.
The write up is compiled by Dr Mohammad Azizur Rahman, Consultant Pulmonologist, Ashiyan Medical College Hospital, Dhaka.